As the use of optical wiring which replaces a microlens or copper wiring used in an image formation optical system of an on-chip color filter, such as an electronic copying machine and a solid-state imaging device, a composition for forming a transparent member is required, which has a high refractive index and is able to form a micro transparent film, transparent wiring and the like.
In particular, a microlens used in a solid-state imaging device has been required to be more miniaturized as the miniaturization of the solid-state imaging device proceeds, and simultaneously to have a high refractive index in order to achieve more effective light focusing. For example, a composition for forming a microlens having a high refractive index or for forming a solid-state imaging device, using silica-coated titanium oxide particles, is disclosed (for example, see Patent Documents 1 and 2). In particular, recently, as a resolution becomes higher, the size of a pixel is accordingly very small, and thus it has been required to collect light more efficiently. For this reason, a microlens having a higher refractive index is required. Further, in order to make more devices in one manufacturing process, the size of a wafer used is increasing, and in that case, coated surface conditions tend to deteriorate.
Meanwhile, Patent Document 3 discloses a dispersion resin having a specific structure, which may enhance dispersibility of an organic pigment for the use of a color filter. In addition, Patent Document 4 discloses a composition for forming a material having a high refractive index, which contains the dispersion resin having a specific structure together with inorganic particles.